JP3480386B2 - Boiling cooling device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boiling cooling device for cooling a heating element by boiling and condensing action of a refrigerant.

[0002]

2. Description of the Related Art As a conventional device, there is an industrial power unit cooler (boiling cooler). In this cooler, a heat generating element such as an IGBT is brought into contact with a heat receiving surface of a refrigerant tank that stores the refrigerant, and heat generated from the heat generating element is transferred to the refrigerant to be transported to a heat radiating section, and an external fluid (eg It is a device that dissipates heat to the air. Here, since the IGBT, which is the heating element, is packaged independently, it can be attached relatively freely to the cooler. However, when the heating element is a computer chip installed on the printed circuit board, if there is a protrusion on the heat receiving surface side of the refrigerant tank that contacts the computer chip or around the refrigerant tank, the protrusion will be a component on the printed circuit board. Or it may interfere with the printed circuit board itself. Therefore, it is desirable that the cooler has a structure having no protrusion on the heat receiving surface side of the refrigerant tank or around the refrigerant tank.

Therefore, the present applicant has filed Japanese Patent Application No. 10-330.
No. 986, the boiling cooling device shown in FIG. 4 was proposed. This device is provided with a flat plate-shaped coolant tank 4, a heat radiating portion 5 is provided on one flat surface side of the coolant tank 4, and a heating element (for example, a computer chip 3) is provided on the other surface (heat receiving surface) of the coolant tank 4. It is a structure to attach. The heat radiating section 5 has a set of header tanks 16 inserted in a direction substantially perpendicular to the refrigerant tank 4,
A heat radiation tube 17 and a heat radiation fin 18 are arranged between both header tanks 16. With this, the heat radiating portion 5 can be accommodated on the one flat surface side within the outer shape of the refrigerant tank 4, so that a boiling cooling device having no protruding portion on the heat receiving surface side of the refrigerant tank 4 and around the refrigerant tank 4 can be configured.

[0004]

However, in the boiling cooling apparatus of the prior application, as shown in FIG. 18, the end portion of the header tank 16 is inserted into the refrigerant tank 4 to be assembled. If the amount of insertion varies, the heat radiation fins 18a that come into contact with the refrigerant tank 4 are crushed, or the heat radiation fins 18a float from the surface of the refrigerant tank 4, which causes a problem of impairing the heat radiation performance. The present invention has been made based on the above circumstances, and an object of the present invention is to provide a boiling cooling device capable of preventing the heat radiation fins from being crushed or lifted to prevent deterioration of heat radiation performance.

[0005]

(Means for Solving the Problems) (Means for Claim 1) A heat radiating tube which is closest to a refrigerant tank via a heat radiating fin is defined as a first heat radiating tube, and is provided between the first heat radiating tube and the refrigerant tank. When the radiating fins to be interposed are the first radiating fins, the first radiating fins are placed in the refrigerant tub so that the distance between the refrigerant tub and the first radiating tube becomes a predetermined value based on the fin height of the first radiating fins. The insertion amount of the header tank to be inserted is regulated. As a result, the insertion amount of the header tank can be maintained at an appropriate value, so that it is possible to prevent the crushing and floating of the first radiating fins.

(Means for Claim 2) In the boiling cooling apparatus according to claim 1, the insertion amount of the header tank can be regulated by bringing the reference surface provided in the header tank into contact with the surface of the refrigerant tank.

(Means for Claim 3) In the boiling cooling apparatus according to claim 1, the amount of insertion of the header tank is such that the end face of the header tank inserted into the refrigerant tank is brought into contact with the wall surface inside the refrigerant tank. Can be regulated by.

(Means of Claims 4 to 7) In the boiling cooling device according to claim 1, the amount of insertion of the header tank can be regulated by the spacer. Specifically, as described in the means of claim 5, the end face of the spacer is brought into contact with the surface of the coolant tank. Alternatively, as described in the means of claim 6, it can be regulated by bringing the end surface of the spacer inserted into the refrigerant tank into contact with the wall surface in the refrigerant tank. Alternatively,
As described in the means of claim 7, it is possible to regulate the insertion amount of the header tank by interposing a spacer between the first heat dissipation tube and the refrigerant tank.

(Means of claim 8) In the boiling cooling apparatus according to claim 1, a heat radiation tube is arranged also on the refrigerant tank side of the first radiation fin, and the heat radiation tube is brought into contact with the surface of the refrigerant tank. The amount of insertion of the header tank can be regulated by.

(Means of Claim 9) In the boiling cooling apparatus according to claim 4, the spacer can be provided integrally with the refrigerant tank by cutting, for example. Alternatively, when a plurality of plate-shaped members are stacked to form a refrigerant tank, each plate-shaped member is provided with a column portion forming a part of the spacer, and the column portions are stacked to provide the spacer. You can also

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. The boiling cooling device 1 of the present embodiment is applied to a computer chip 3 (hereinafter abbreviated as chip 3) installed on a printed circuit board 2 (see FIG. 6), and as shown in FIG. A coolant tank 4 that stores (for example, water, alcohol, fluorocarbon, chlorofluorocarbon, etc.), and a heat dissipation unit 5 that releases the heat of the refrigerant vapor boiled by receiving the heat of the chip 3 to the external fluid in the coolant tank 4, Manufactured by integral brazing.

First, the basic structure of the coolant tank 4 and the heat radiating portion 5 will be described. A) The refrigerant tank 4 is composed of a thin container 6 formed of a metal material (for example, aluminum) having excellent thermal conductivity and a plate-shaped lid component 7, and is used in an upright state as shown in FIG. . As shown in FIG. 5, the thin container 6 has a vertically long rectangular planar shape, one side in the thickness direction (back side in FIG. 5) is a flat surface and is used as a mounting surface (heat receiving surface) of the chip 3, and the other side. On the side, a boiling space 8 described below, a set of header connection parts 9 and 10, a liquid return passage 11, and a refrigerant injection part 1 are provided.
Two are provided. In addition, at both upper and lower ends of the thin container 6, there are provided a plurality of holes 13 through which connection parts (for example, screws, bolts, etc.) for fixing the chip 3 to the surface (flat surface) of the thin container 6 are passed. There is.

The boiling space 8 is a space where the liquid refrigerant boils when receiving the heat of the chip 3, and is provided in the entire central portion of the thin container 6. In this boiling space 8, a large number of prisms 14 are arranged in a grid pattern at regular intervals, and the entire boiling space 8 forms a coolant passage partitioned like a grid. The large number of prisms 14 provided in the boiling space 8 also function as reinforcing ribs for ensuring the strength of the refrigerant tank 4. The header connecting portions 9 and 10 are portions to which the header tank 16 (described below) of the heat radiating portion 5 is connected.
A space corresponding to the cross-sectional shape of is provided. One header connecting portion 9 is provided adjacent to the upper right side of the boiling space 8 and communicates with the boiling space 8. The other header connection portion 10 is provided on the upper left side of the boiling space 8 and communicates with the boiling space 8 through the liquid return passage 11.

The liquid return passage 11 is a passage for returning the condensed liquid liquefied in the heat radiating portion 5 to the boiling space 8, and is provided so as to extend downward from the lower portion of the other header connecting portion 10 and to the uppermost portion of the boiling space 8. It leads to the bottom. The coolant injection part 12 is a coolant tank 4
Is an injection passage for injecting the refrigerant into the inside (boiling space 8), is provided below one header connecting portion 9 and communicates with the boiling space 8. The boiling space 8, the header connection parts 9, 10, the liquid return passage 11, the refrigerant injection part 12, etc. are
It can be formed by cutting, electric discharge machining, forging, casting or the like.

The lid part 7 is made of, for example, a clad material integrally formed with a brazing material on the surface thereof, completely covers the other side of the thin container 6, and a boiling space 8 and a liquid return passage provided in the thin container 6. The opening surface of 11 is closed. However, the lid component 7
An insertion port (not shown) for inserting the end portion of the header tank 16 is opened on both upper sides of the above, and the insertion ports communicate with the header connection portions 9 and 10 of the thin container 6, respectively. In addition, a round hole (not shown) which communicates with the refrigerant injection part 12 provided in the thin container 6 is opened in the lid part 7 at the lower part of one insertion port, and the injection pipe 15 is connected to this round hole. The injection pipe 15 is an injection port for injecting the refrigerant into the refrigerant tank 4, and after injecting a predetermined amount of the refrigerant into the refrigerant tank 4 through the injection pipe 15, the tip opening portion of the injection pipe 15 is sealed.

B) The heat dissipating section 5 includes a set of header tanks 16
(16A, 16B) and a core portion (described below) are provided, and are assembled substantially perpendicular to the refrigerant tank 4. The set of header tanks 16 is a steam-side header tank 1 into which the refrigerant vapor that has boiled due to the heat of the chips 3 in the boiling space 8 of the refrigerant tank 4 flows in.
6A and a liquid side header tank 16B into which the condensed liquid liquefied in the core part flows, and as shown in FIG. 1, they are configured by combining an inner header plate 16a and an outer header plate 16b, respectively. Steam side header tank 16
A is arranged such that one end portion in the longitudinal direction is inserted into the inside of the refrigerant tank 4 (one header connection portion 9) from one insertion port of the lid component 7 and extends substantially vertically to the lid component 7. To be done. The liquid-side header tank 16B has one end in the longitudinal direction inserted into the inside of the refrigerant tank 4 (the other header connection portion 10) from the other insertion port of the lid component 7 and extends in a direction substantially perpendicular to the lid component 7. It is placed in a closed state.

The core portion includes a plurality of heat radiation tubes 17,
The heat radiation fins 18 are interposed between the heat radiation tubes 17, and an external fluid (for example, air) is supplied through a duct 19 as shown in FIG. Heat dissipation tube 17
Is provided in a flat shape having a thin thickness with respect to the width of the surface with which the radiation fins 18 come into contact.
Multiple header tanks 16 are installed in parallel between B
It communicates with A and 16B. The radiating fins 18 are formed by alternately bending a thin metal plate (for example, an aluminum plate) having excellent thermal conductivity to form a wavy shape.
Is thermally bonded to the surface of.

As shown in FIG. 6, the duct 19 is installed so as to pass through the outside of the header tanks 16A and 16B and surround the heat dissipation portion 5. It should be noted that the duct 19 does not cause a large gap between the duct 19 and the outer surface of each of the header tanks 16A and 16B, or each of the header tanks 16A and 16B.
Each header tank 16 in a state of being substantially in contact with the outer surface of B
A and 16B are arranged along the outer surface. Duct 1
The external fluid introduced into the core portion through 9 flows from the lower side to the upper side as indicated by an arrow in FIG.

Next, the operation of this embodiment will be described. The liquid refrigerant in the refrigerant tank 4 receives the heat of the chip 3 and boils, enters the steam-side header tank 16A from the boiling space 8 and flows from the steam-side header tank 16A to each radiating tube 17. The refrigerant vapor flowing through the heat dissipation tube 17 is cooled by the external fluid introduced into the core portion through the duct 19 and condensed inside the heat dissipation tube 17. The condensed refrigerant enters the liquid-side header tank 16B as droplets, and further returns from the liquid-side header tank 16B to the boiling space 8 through the liquid return passage 11 in the refrigerant tank 4. The flow of the refrigerant in this operation is shown in FIG.

Next, an embodiment in which the insertion amount of the header tank 16 inserted into the refrigerant tank 4 is regulated will be described. (First Embodiment) FIGS. 1 to 3 are sectional views showing a method of regulating the insertion amount of the header tank 16. In this embodiment, FIG.
At the bottom, the heat dissipation tube 17a at the bottom (first of the present invention
Of the heat radiation tube) and the coolant tank 4 is inserted into the coolant tank 4 so as to have a predetermined value based on the fin height of the heat radiation fin 18a (first heat radiation fin of the present invention) at the lowermost stage. The insertion amount of the header tank 16 is regulated. The above-mentioned "predetermined value" is substantially the same as the proper fin height of the radiation fin 18a (for example, fin height ± 0.0).
5).

As a means for regulating the insertion amount of the header tank 16, as shown in FIG. 1, a step surface 20 (reference surface of the present invention) is provided on the inner header plate 16a constituting the header tank 16, and this step By bringing the surface 20 into contact with the upper surface of the refrigerant tank 4, the insertion amount of the header tank 16 is regulated. Alternatively, as shown in FIG. 2, the outer header plate 1
6b is provided with a stepped surface 20, and the stepped surface 20 is connected to the refrigerant tank 4
The insertion amount of the header tank 16 may be regulated by abutting on the upper surface of the. In this way, when the insertion amount of the header tank 16 is restricted by only one of the header plates 16a or 16b, both header plates 16a, 16b
By disposing the positioning portion 16c on the base plate and assembling the header plates 16a and 16b at predetermined positions by the positioning portion 16c, the displacement of the header plates 16a and 16b can be prevented.

Alternatively, as shown in FIG. 3, a step surface 20 is provided on each of the header plates 16a and 16b,
The step surface 20 may be brought into contact with the upper surface of the refrigerant tank 4 to regulate the insertion amount of the header tank 16. In this case, the above-mentioned positioning part 16c is unnecessary. According to the configuration of this embodiment, the insertion amount of the header tank 16 can be maintained at an appropriate value without variation, so that the radiation fins 18a interposed between the refrigerant tank 4 and the lowermost radiation tube 17a. It is possible to prevent the occurrence of crushing and floating, and to prevent deterioration of heat dissipation performance.

(Second Embodiment) FIGS. 8 to 10 are sectional views showing a method of regulating the insertion amount of the header tank 16. In this embodiment, as shown in FIG. 8, the insertion amount of the header tank 16 is regulated by bringing the end surface of the inner header plate 16a inserted into the refrigerant tank 4 into contact with the bottom surface of the refrigerant tank 4. Alternatively, as shown in FIG. 9, the insertion amount of the header tank 16 may be regulated by bringing the end surface of the outer header plate 16b into contact with the bottom surface of the refrigerant tank 4. The inner header plate 16a or the outer header plate 16b is arranged so as not to prevent communication between the refrigerant tank 4 and the header tank 16.
You may provide the opening part 21 at the edge part.

As described above, when the insertion amount of the header tank 16 is restricted by only one of the header plates 16a or 16b, both the header plates 16a and 16b are positioned by the positioning portion 16c as in the first embodiment. Both header plates 16a, 1
The shift of 6b can be prevented. Alternatively, as shown in FIG. 10, both the end surface of the inner header plate 16a and the end surface of the outer header plate 16b may be brought into contact with the bottom surface of the refrigerant tank 4 to regulate the insertion amount of the header tank 16. In this case, the positioning portion 16 is attached to both header plates 16a and 16b.
It is not necessary to provide c.

(Third Embodiment) FIGS. 11 to 13 are sectional views showing a method of regulating the insertion amount of the header tank 16. In this embodiment, the spacer 22 is used to make the header tank 16
Regulates the amount of insertion. The spacer 22 is, for example, as shown in FIG.
As shown in FIG. 1, it is interposed between the step portion 23 provided on the inner header plate 16 a and the upper surface of the coolant tank 4. In this case, the insertion amount of the header tank 16 can be regulated by the lower end surface of the spacer 22 coming into contact with the upper surface of the refrigerant tank 4. Alternatively, as shown in FIG. 12, the spacer 22 may be interposed between the step portion 23 provided on the inner header plate 16 a and the bottom surface of the coolant tank 4. In this case, spacer 2
The lower end surface of 2 comes into contact with the bottom surface in the refrigerant tank 4, so that the insertion amount of the header tank 16 can be regulated.

It is needless to say that the outer header plate 16b may be provided with the step portion 23 and the spacer 22 may be interposed between the step portion 23 and the refrigerant tank 4 to regulate the insertion amount of the header tank 16. Yes. In this way, when the spacer 22 is interposed between one of the header plates 16a or 16b and the refrigerant tank 4, both header plates 16a and 16b are assembled at a predetermined position by the positioning portion 16c. Header plates 16a, 1
The shift of 6b can be prevented. Alternatively, as shown in FIG. 13, the inner header plate 16 inserted into the refrigerant tank 4
Spacers 22 may be interposed between a and both end surfaces of the outer header plate 16b and the bottom surface of the coolant tank 4. In this case, the positioning portion 16 is attached to both header plates 16a and 16b.
c is unnecessary.

(Fourth Embodiment) FIG. 14 shows a header tank 16
It is sectional drawing which shows the method of controlling the insertion amount of. In the present embodiment, as shown in FIG. 14, the heat dissipation tube 17b is also disposed below the heat dissipation fins 18a arranged at the bottom, and the heat dissipation tube 17b is brought into contact with the upper surface of the refrigerant tank 4 to make the header tank. 16 plug-ins are regulated. In this case, like the other radiation fins 18, the radiation fins 18a in the lowermost stage can be held between the radiation tubes 17a and 17b, so the radiation fins 18 arranged in the lowermost stage.
It is possible to prevent crushing and floating of a. An appropriate spacer may be arranged below the heat dissipating fins 18a arranged at the bottom, instead of the heat dissipating tube 17b.

(Fifth Embodiment) FIG. 15 shows a header tank 16
It is sectional drawing which shows the method of controlling the insertion amount of. In the present embodiment, as shown in FIG. 15, a lid receiving portion 24 for regulating the insertion amount of the header tank 16 is provided in the lid component 7 forming the refrigerant tank 4. The insertion amount of the header tank 16 is restricted by the end surface of the header tank 16 contacting the header receiving portion 24 of the lid component 7. With this structure, since the lower end portion of the header tank 16 can be brazed to the header receiving portion 24, it is expected that the joint strength will be improved.

(Sixth Embodiment) FIGS. 16 and 17 are sectional views showing a method of regulating the insertion amount of the header tank 16. The present embodiment is an example in which a spacer 25 for restricting the insertion amount of the header tank 16 is provided inside the refrigerant tank 4, and the spacer 25 is provided integrally with the refrigerant tank 4.
In this case, for example, by forming the refrigerant tank 4 by cutting or cold forging, as shown in FIG.
5 can be provided integrally with the thin container 6 of the refrigerant tank 4. Further, as shown in FIG. 17, when the refrigerant tank 4 is configured by stacking a plurality of plate-shaped members 4a, each plate-shaped member 4
It is possible to provide the spacers 25 by providing the pillar portions 4b that form a part of the spacers 25 in a, and stacking the pillar portions 4b.

According to the structure of this embodiment, the lower end surface of the header tank 16 is provided with the spacer 25 as in the case of the fifth embodiment.
Since it can be brazed to the upper end surface of, the joint strength can be improved. In the structure of the present embodiment, a slight gap is secured between the lower end surface of the header tank 16 and the upper end surface of the spacer 25 in the assembled state before brazing, and the brazing material is used during brazing. The header tank 16 sinks in contact with the spacer 25 when melted.
That is, the height dimension of the spacer 25 is set in consideration of the amount of the brazing material melted during brazing.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a method of regulating the insertion amount of a header tank (first embodiment).

FIG. 2 is a cross-sectional view showing a method of regulating the insertion amount of the header tank (first embodiment).

FIG. 3 is a cross-sectional view showing a method of regulating the insertion amount of the header tank (first embodiment).

FIG. 4 is a perspective view of a boiling cooling device.

FIG. 5 is a plan view of a thin container.

FIG. 6 is a perspective view showing a usage state of the boiling cooling device.

FIG. 7 is a perspective view of a boiling cooling device showing a flow of a refrigerant.

FIG. 8 is a cross-sectional view showing a method of regulating the insertion amount of the header tank (second embodiment).

FIG. 9 is a cross-sectional view showing a method of regulating the insertion amount of the header tank (second embodiment).

FIG. 10 is a cross-sectional view showing a method of regulating the insertion amount of the header tank (second embodiment).

FIG. 11 is a cross-sectional view showing a method of regulating the insertion amount of the header tank (third embodiment).

FIG. 12 is a cross-sectional view showing a method of regulating the insertion amount of the header tank (third embodiment).

FIG. 13 is a cross-sectional view showing a method of regulating the insertion amount of the header tank (third embodiment).

FIG. 14 is a cross-sectional view showing a method of regulating the insertion amount of the header tank (fourth embodiment).

FIG. 15 is a cross-sectional view showing a method of regulating the insertion amount of the header tank (fifth embodiment).

FIG. 16 is a cross-sectional view showing a method of regulating the insertion amount of the header tank (sixth embodiment).

FIG. 17 is a sectional view showing a method of restricting the insertion amount of the header tank (sixth embodiment).

FIG. 18 is a cross-sectional view showing a connecting portion between a refrigerant tank and a header tank (prior application technology).

[Explanation of symbols]

1 boiling cooling system 4 Refrigerant tank 5 Heat sink 16 header tank 17 Heat dissipation tube 17a Radiation tube at the bottom (first radiation tube) 18 radiating fins 18a Radiation fin at the bottom (first radiation fin) 20 Step surface (reference surface provided on header tank) 22 Spacer (third embodiment) 25 Spacer (sixth embodiment)

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takahide Ohara 1-1, Showa-cho, Kariya city, Aichi prefecture, Denso Co., Ltd. (72) Inventor Akihiro Maeda 1-1-1-1, Showa-cho, Kariya city, Aichi prefecture, Denso company ( 72) Inventor Eitaro Tanaka, 1-1, Showa-cho, Kariya city, Aichi, Japan DENSO CORPORATION (56) References JP 9-107058 (JP, A) JP 10-335549 (JP, A) JP 2000-156444 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01L 23/427 H05K 7/20

Claims (9)

(57) [Claims] 1. A refrigerant tank for storing a liquid refrigerant therein, a set of header tanks connected to the refrigerant tank, a heat radiation tube for communicating both header tanks, and a heat radiation fin for contacting the surface of the heat radiation tube. A heat dissipation part that is assembled by inserting the end part of the header tank into the refrigerant tank, and heats the refrigerant vapor boiled by receiving the heat of the heating element in the refrigerant tank with the external fluid in the heat dissipation part. In a boiling cooling device that is liquefied by replacement, the heat dissipation tube closest to the refrigerant tank via the heat dissipation fin is a first heat dissipation tube, and is interposed between the first heat dissipation tube and the refrigerant tank. When the radiating fins to be used are the first radiating fins, the gap between the coolant tank and the first radiating tube becomes a predetermined value based on the fin height of the first radiating fins. Refrigerant tank A boiling cooling device, wherein the amount of the header tank inserted into the inside is regulated. 2. The boiling cooling device according to claim 1, wherein the insertion amount of the header tank is regulated by bringing a reference surface provided in the header tank into contact with the surface of the refrigerant tank. Characteristic boiling cooling device. 3. The boiling cooling device according to claim 1, wherein the insertion amount of the header tank is regulated by contacting an end surface of the header tank inserted into the refrigerant tank with a wall surface inside the refrigerant tank. The boiling cooling device is characterized by being. 4. The boiling cooling device according to claim 1, further comprising a spacer that regulates an insertion amount of the header tank. 5. The boiling cooling device according to claim 4, wherein the insertion amount of the header tank is regulated by bringing the end surface of the spacer into contact with the surface of the refrigerant tank. Cooling system. 6. The boiling cooling device according to claim 4, wherein the insertion amount of the header tank is regulated by contacting an end surface of the spacer inserted into the refrigerant tank with a wall surface inside the refrigerant tank. A boiling cooling device characterized in that 7. The boiling cooling apparatus according to claim 4, wherein the insertion amount of the header tank is regulated by interposing the spacer between the first heat radiation tube and the refrigerant tank. Boil cooling device. 8. The boiling cooling apparatus according to claim 1, wherein the heat radiation tube is also arranged on the refrigerant tank side of the first heat radiation fin, and the heat radiation tube is brought into contact with the surface of the refrigerant tank. An evaporative cooling device in which the insertion amount of the header tank is regulated. 9. The boiling cooling device according to claim 4, wherein the spacer is provided integrally with the refrigerant tank.